Injection systems are used in the petrochemical industry for a number of purposes. It is frequently desirable to have an injection system capable of injecting at least one additive into a product line. The prior art teaches a manifold injection system. Typically, when one wishes to change the additive that is being mixed into the product, one flushes the injection manifold.
Frequently, such injection systems are used in fuel storage and loading terminals. Fuel storage and loading terminals typically store one or more products and have multiple loading arms through which to load portable containers with those products. Manifold injection systems are used on or near the loading arm to inject gasoline or diesel additives and dyes into the products as they are pumped into the containers.
The prior art teaches the use of an additive injection system having an injection manifold connected at one end to a valve and a large flush pump and at the other end to the product line. The large flush pump draws from earlier in the product line or from a similar product line and services all of the injection manifolds at a location. When flush is desired of any particular injection manifold, the valve for that injection manifold is opened, allowing the flush pump to pump product through the injection manifold. The drawbacks to the prior art include lack of flexibility and the great expense associated with the large flush pump and the plumbing from that large flush pump to multiple injection manifolds. The prior system also does not insure flushing with a product identical to the product serviced by the injection manifold.
It would be a benefit to provide a more flexible system for flushing an injection system, particularly one capable of being expanded (e.g. having injection manifolds added) or contracted (e.g. removing injection manifolds) as demand dictates. It would also be a benefit to provide a more cost effective manner of constructing an injection system with flushing capabilities. It would be a further benefit to provide a flushing system that flushed the injection manifold with the exact product serviced by that injection manifold.